The present invention relates in general to a regeneration system for use with a hydraulic power circuit that will dump and roll back the bucket of an earth-working machine. In particular, the regeneration system supplements the hydraulic system's pump when the bucket is being dumped and is pulled downwardly by gravity.
Modern earth-working machines typically have implements, such as buckets, that are powered by hydraulic systems. These systems may raise or lower the vertical position of an implement, actuate an implement, or move an implement about a pivot point. In a hydraulic system for powering the bucket of an earth-working machine, the system may raise or lower the vertical position of the bucket and dump and roll back the bucket. These systems have a piston connected to the bucket and disposed in an hydraulic cylinder with power chambers on both sides of the piston for powering the piston rearwardly and forwardly. In order to maintain adequate control over the speed of movement of the piston, it is important that these power chambers are adequately filled with hydraulic fluid. Problems can arise with an action such as dumping the bucket of an earth-working machine. These buckets are typically of large mass, and when they are moved to dump, the force of gravity will aid in the bucket moving downwardly. Since the bucket is moving under more than the force of the hydraulic fluid powering the piston, the piston will begin to move with the bucket faster than the hydraulic fluid could independently power it. When this happens, the hydraulic pump may not be able to supply sufficient hydraulic fluid to the power chamber to keep it adequately filled. This could result in a partially filled hydraulic chamber that will not provide adequate control to the operator.
It is thus an object of the present invention to provide a hydraulic system for powering the bucket of an earth-working machine that supplements the hydraulic pump when the bucket is being moved to dump and is moving downwardly due to gravity.
It is further an object of the present invention to utilize a hydraulic regeneration system for forcing cylinder return fluid to join fluid from the hydraulic pump for insuring an adequate supply to the cylinder when the implement is moved by gravity or another external force.
Moreover, it is an object to achieve these goals with a hydraulic system that is relatively simple.
These and other objects are addressed by the present invention.